Add to ORKG1st ed. Topographic map of Lake Johnston region, Western Australia, showing classes of roads, telephone lines, electric power stations, railway lines with stations and sidings, aerodromes, emergency landing grounds, seaplane bases and mooring areas. Relief shown by hachures and spot heights.; "1942".; "This map is compiled from the latest Commonwealth and State information and is not the result of precise military survey".; "This map is an official document. If found, it must handed in to the nearest military headquarters or police station".; Place name index on verso.; Includes index to adjoining sheets and grid referencing guide.; Also available online http://nla.gov.au/nla.map-vn5760951.Refer to this map as 4 mile strategic sereis Austra...